Sutro Tower, Inc. • San Francisco, California

Sutro513 Page 1 of 3

Statement of Hammett & Edison, Inc., Consulting Engineers

The firm of Hammett & Edison, Inc., Consulting Engineers, has been retained by Sutro Tower, Inc. to evaluate RF exposure levels near the Sutro Tower broadcast site, 1 La Avanzada Street, San Francisco, California, for compliance with appropriate guidelines limiting human exposure to radio frequency electromagnetic fields.

Background Information

Sutro Tower is located near Mt. Sutro in San Francisco, California, and currently supports the transmitting facilities for eleven DTV stations and three FM stations. As part of the final DTV antenna installation project, Sutro Tower agreed to provide the neighborhood associations with measurement data of existing RF exposure levels at 200 locations within a 1,000-foot radius of the tower within two weeks of the activation of any new DTV antenna, or within two weeks of any DTV antenna power increase, or every three years, whichever is earliest.

Prevailing Exposure Standards

The U.S. Congress requires that the Federal Communications Commission (“FCC”) evaluate its actions for possible significant impact on the environment. In Docket 93-62, effective October 15, 1997, the FCC adopted the human exposure limits for field strength and power density recommended in Report No. 86, “Biological Effects and Exposure Criteria for Radiofrequency Electromagnetic Fields,” published in 1986 by the Congressionally chartered National Council on Radiation Protection and Measurements (“NCRP”). Separate limits apply for occupational and public exposure conditions, with the latter limits generally five times more restrictive. The more recent standard, developed by the Institute of Electrical and Electronics Engineers and approved as American National Standard ANSI/IEEE C95.1-2006, “Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz,” includes similar exposure limits. A summary of the FCC’s exposure limits is shown in Figure 1. These limits apply for continuous exposures and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health.

Measurement Procedure

The site was visited by the undersigned engineer during regular business hours on August 6, 2014, a non-holiday weekday. Measurements were made at 208 locations within a 1,000-foot radius of Sutro Tower, as shown in Figure 2, including all residential streets. Measurements were taken at a typical spacing of about 60–75 feet along the streets, although variations occurred due to topography and street layout. Measurements were made using a Narda Type NBM-520 Broadband Field Meter with

Sutro Tower, Inc. • San Francisco, California

Sutro513

Page 2 of 3

Type EF-0391 and Type EA-5091 Isotropic Broadband Electric Field Probes (Serial Nos. D-0454 and

01035, respectively). All meters and probes were under current calibration by manufacturer. The

Type EF-0391 probe provides results in volts/meter (V/m) and is calibrated for exposure of levels

down to 0.2 V/m (0.005% of the most restrictive public limit); measurement results using that

instrument are expressed as a percentage of the most restrictive FCC limit (0.2 mW/cm2). The Type

EA-5091 probe is capable of providing results directly as a percent of the applicable FCC exposure

limit. Both probes are broadband devices, which means that they measure all radio frequency sources,

not just the broadcast operations at Sutro Tower.

The specifications of the main DTV and FM antennas, as operating during the measurements, are as

follows:

Effective Center Height

Station Channel Radiated Power Antenna Make & Model Above Sea Level

KGO-TV D07 24 kW Dielectric TCL-6A7-S 544.2 m

KOFY-TV D19 568 Dielectric TFU-30DSC/VP-R 4C190 519.0

KPIX-TV D29 1,000 Dielectric TUM-C5SP-14/60H-2-T-R 542.6

KQED D30 1,000 Dielectric TUM20-C5SP-14/60H-2-R-T 542.6

KMTP-TV D33 480 Dielectric TUM20-C5SP-14/60H-2-R-T 542.6

KFSF-DT D34 370 Dielectric TFU-26DSC/VP-R P190 523.7

KRON-TV D38 1,000 Dielectric TUM-C5SP-14/60H-2-T-R 542.6

KCNS D39 1,000 Dielectric TUM20-C5SP-14/60H-2-R-T 542.6

KCSM-TV D43 500 Dielectric TUM20-C5SP-14/60H-2-R-T 542.5

KTVU D44 1,000 Dielectric TUM-C5SP-14/60H-2-T-R 542.0

KBCW D45 1,000 Dielectric TFU-19JSC/VP-R CT150 SP 521.4

KOIT(FM) 243 24 Antenna Concepts ATI6M 511

KSOL(FM) 255 6.1 ERI LPX-3E-SP 440

KFOG(FM) 283 7.1 Harris FMH-2AE-HW 490

Measurement Results

The maximum RF level measured at any of the 208 locations surrounding Sutro Tower was 6.0% of

the most restrictive FCC public exposure limit. A tabulation of measurement results at each of those

locations is provided in Figure 3.

Conclusion

It is my professional opinion that the TV and FM broadcast stations at Sutro Tower continue to

comply with prevailing standards for limiting public exposure to radio frequency energy.

Sutro Tower, Inc. • San Francisco, California

Sutro513 Page 3 of 3

Figures

In carrying out these engineering studies, the following attached figures were prepared under my direct supervision: 1. Summary of FCC RF exposure guidelines 2. Map showing measurement locations 3. Table showing measurement results.

_________________________________ Rajat Mathur, P.E. August 29, 2014

FCC Radio Frequency Protection Guide

FCC GuidelinesFigure 1

Frequency (MHz)

1000

100

10

1

0.1

0.1 1 10 100 103 104 105

Occupational Exposure

Public Exposure

PCSCell

FM

Pow

erD

ensi

ty(m

W/c

m2 )

The U.S. Congress required (1996 Telecom Act) the Federal Communications Commission (“FCC”)to adopt a nationwide human exposure standard to ensure that its licensees do not, cumulatively, havea significant impact on the environment. The FCC adopted the limits from Report No. 86, “BiologicalEffects and Exposure Criteria for Radiofrequency Electromagnetic Fields,” published in 1986 by theCongressionally chartered National Council on Radiation Protection and Measurements (“NCRP”).Separate limits apply for occupational and public exposure conditions, with the latter limits generallyfive times more restrictive. The more recent standard, developed by the Institute of Electrical andElectronics Engineers and approved as American National Standard ANSI/IEEE C95.1-2006, “SafetyLevels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to300 GHz,” includes similar limits. These limits apply for continuous exposures from all sources andare intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, orhealth.

As shown in the table and chart below, separate limits apply for occupational and public exposureconditions, with the latter limits (in italics and/or dashed) up to five times more restrictive:

Frequency Electromagnetic Fields (f is frequency of emission in MHz) Applicable

Range(MHz)

ElectricField Strength

(V/m)

MagneticField Strength

(A/m)

Equivalent Far-FieldPower Density

(mW/cm2)

0.3 – 1.34 614 614 1.63 1.63 100 1001.34 – 3.0 614 823.8/ f 1.63 2.19/ f 100 180/ f2

3.0 – 30 1842/ f 823.8/ f 4.89/ f 2.19/ f 900/ f2 180/ f2

30 – 300 61.4 27.5 0.163 0.0729 1.0 0.2300 – 1,500 3.54 f 1.59 f f /106 f /238 f/300 f/1500

1,500 – 100,000 137 61.4 0.364 0.163 5.0 1.0

Higher levels are allowed for short periods of time, such that total exposure levels averaged over six orthirty minutes, for occupational or public settings, respectively, do not exceed the limits, and higherlevels also are allowed for exposures to small areas, such that the spatially averaged levels do notexceed the limits. However, neither of these allowances is incorporated in the conservative calculationformulas in the FCC Office of Engineering and Technology Bulletin No. 65 (August 1997) forprojecting field levels. Hammett & Edison has built those formulas into a proprietary program thatcalculates, at each location on an arbitrary rectangular grid, the total expected power density from anynumber of individual radio sources. The program allows for the description of buildings and uneventerrain, if required to obtain more accurate projections.

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Sutro513 Figure 2

Sutro Tower, Inc. • San Francisco, California

Measured Power Density Levels August 6, 2014

Percent Percent Percent Location FCC Limit* Location FCC Limit* Location FCC Limit*

* Expressed as percent of most restrictive FCC limit of 0.2 mW/cm2, except as noted. † Expressed as percent of applicable public limit for frequencies involved; Type EA-5091

probe used.

Sutro513 Figure 3A

1 1.3 2 0.90 3 0.76 4 0.48 5 0.38 6 1.9 7 1.9 8 1.3 9 1.2 10 0.97 11 1.0 12 0.58 13 0.70 14 0.53 15 0.58 16 0.48 17 0.53 18 0.53 19 0.26 20 0.26 21 0.22 22 0.64 23 1.4 24 1.5 25 1.2 26 0.76 27 0.53 28 0.64 29 0.83 30 0.76 31 0.97 32 1.4 33 0.97 34 1.3 35 0.48 36 0.43 37 0.58 38 1.0 39 0.48 40 0.64

41 1.1 42 1.1 43 1.6 44 1.6 45 2.0 46 2.2 47 1.6 48 1.4 49 1.0 50 1.7 51 1.9 52 1.8 53 1.8 54 0.83 55 0.90 56 1.4 57 2.3 58 2.5 59 2.0 60 1.2 61 1.0 62 1.0 63 0.90 64 0.70 65 4.2 66 2.2 67 4.2 68 1.7 69 1.1 70 0.76 71 0.53 72 2.6 73 5.4 74 0.97 75 2.1 76 2.7† 77 1.4 78 2.8 79 1.9 80 4.0

81 1.7 82 0.58 83 0.48 84 0.58 85 0.70 86 0.83 87 1.8 88 1.9 89 2.3 90 4.2 91 6.0† 92 5.0† 93 5.3 94 5.4 95 4.2 96 4.5 97 2.1 98 1.4 99 2.0 100 1.7 101 1.8 102 0.76 103 1.0 104 0.97 105 0.43 106 2.3 107 3.1 108 2.1 109 0.70 110 0.76 111 1.5 112 0.64 113 0.58 114 0.70 115 0.58 116 0.76 117 0.90 118 0.97 119 0.48 120 0.38

Sutro Tower, Inc. • San Francisco, California

Measured Power Density Levels August 6, 2014

Percent Percent Percent Location FCC Limit* Location FCC Limit* Location FCC Limit*

* Expressed as percent of most restrictive FCC limit of 0.2 mW/cm2, except as noted. † Expressed as percent of applicable public limit for frequencies involved; Type EA-5091

probe used.

Sutro513 Figure 3B

121 0.48 122 0.58 123 0.70 124 0.76 125 1.5 126 1.5 127 1.6 128 1.6 129 1.5 130 1.9 131 1.0 132 0.70 133 2.9 134 4.5 135 4.7† 136 5.0† 137 2.9 138 2.2 139 2.3 140 1.9 141 0.97 142 0.19 143 0.90 144 0.70 145 0.58 146 0.48 147 0.43 148 0.64 149 0.97 150 0.43 151 0.58 152 0.58 153 1.0 154 1.0 155 0.64 156 0.53 157 0.70 158 0.83 159 0.70 160 0.76

161 1.7 162 0.38 163 2.0 164 1.8 165 0.70 166 0.90 167 1.4 168 0.97 169 1.2 170 1.7 171 2.9 172 4.2 173 2.3 174 2.9 175 2.7 176 0.76 177 1.7 178 1.9 179 2.5 180 4.0† 181 4.6† 182 4.2† 183 2.7† 184 2.5 185 1.5 186 0.64 187 0.70 188 0.70 189 0.43 190 0.48 191 0.70 192 0.53 193 0.58 194 0.34 195 0.26 196 0.38 197 0.48 198 0.53 199 0.34 200 0.16

201 0.26 202 0.13 203 0.48 204 0.53 205 1.4 206 2.0 207 4.0 208 2.6